"Maximizing irrigation system efficiency with silver-stabilized disinfectant"

"We often hear the claim, 'We cannot use Intra Hydropure because we are using biostimulants in our drip or sprinkler systems.' Our first thought: all the more reason to use Intra Hydropure", says Claudia Weick with Intracare.

She explains Intra Hydropure is a unique silver-stabilized disinfectant based on hydrogen peroxide. "When reacting with organic compounds, it slowly decomposes in water and oxygen. It will react with all organic substances inside the irrigation systems. This trait results in a biofilm-free irrigation system, creating a smooth surface in your kilometres of pipelines in the greenhouse."

Biofilm might seem just a dead slimy layer but this is not the case. Biofilm is an engineered city of micro-organisms and minerals. The fertilizers in the irrigation water passing through serve as nutrients for the biofilm to keep a steady growth. When organic biostimulants are added to the mixture, they can adhere to the biofilm, creating larger obstructions that can easily block drip emitters, micro-sprinklers, or other components of the irrigation system.

Less efficiency of nutrients
"Besides the danger of blocked drippers, there will be a reduced efficiency of your biostimulants in presence of a biofilm", Claudia continues, showing what happens inside the drip line with nutrients and organic biostimulants when biofilm is present. "You dose a certain amount of product or fertilizer at the beginning of the line, but when lines are dirty, nutrients will deposit on the biofilm and eventually they will not end up with the plants. In that case, the uniformity and efficacy of the supplied supplements will be less."

Figure 1. Overview of two dripping lines. The line above has biofilm on the surface on the inside of the irrigation system. Biostimulants and nutrients (orange) are absorbed by the biofilm and do not end up at the plants. The bottom line is clean from the beginning to the end, making sure nutrients are distributed more homogeneous to all the plants.

Solution: alternate Intra Hydropure and biostimulants
Many of the biostimulants used nowadays are based on organic compounds, says Claudia. "For example, products based on positive bacteria or fungi, or products containing seaweed extract. The direct combination of Intra Hydropure and these products is indeed not favourable and should be prevented. However, these biostimulant products are often not used continuously. Sometimes they are only given a few days per growth cycle, which is why the organic biostimulants can easily be combined with Intra Hydropure."

Use Intra Hydropure from the start of production with every watering, she advises. "In this way you keep the lines clean from any biofilm. Clean lines make sure that when you dose the biostimulant, it will reach the first and the last plant in line with the same amount. 24 hours before applying the organic biostimulant, stop dosing Intra Hydropure. One or two days after applying the biostimulant, you start using Intra Hydropure again, to make sure residues of the biostimulant do not stay in the irrigation system. This prevents the formation of biofilm and keeps the lines clean."

Figure 2. An example planning for combining Intra Hydropure with an organic biostimulant in the first two weeks of production.

How to use both products
According to Claudia, the correct application is to use Intra Hydropure from the start of production with every watering. "24 hours before applying the organic biostimulant, stop dosing Intra Hydropure. Dose the biostimulant. And one or two days after applying the biostimulant, you start using Intra Hydropure again, to make sure residues of the biostimulant do not stay in the irrigation system. This will prevent the formation of biofilm and will keep the lines clean."

The number of days you need to stop dosing Intra Hydropure depends on the total volume of water given to the plants per day. "Do not forget it can take days before the biostimulant has reached the last dripper. Especially when you give low amounts of water per day per plant in the beginning of the season."